The present invention relates to a solder ball loading method and a solder ball loading unit for loading solder balls, which are to turn to solder bumps, on a printed wiring board.
The solder bumps are used to connect a package substrate with an IC chip. The solder bumps are formed in following process.
(1) Process of printing flux on a connection pad formed on the package substrate
(2) Process of loading the solder ball on the connection pad on which flux is printed
(3) Process of forming the solder bump from the solder ball by reflow.
For example, printing technology described in the patent document 1 is used in the process of loading the aforementioned solder ball on the connection pad. According to this printing technology, a ball arranging mask 116 provided with an opening 116a at each position corresponding to a connection pad 75 is loaded on a printed wiring board 30 and a solder ball 78s is dropped onto the connection pad 75 with a squeegee 124.
Prior art: JP 2001-267731 A is incorporated herein by reference.